I always try to make four attachment pints to secure the gas tank to the frame and I always use rubber insulation to prevent ckracking. There is no shortcuts to happiness....
Closeup of the bung under the tank.
The front mount is made out of hevy steel, and used the old mounting place. No extra holes drilled in the frame.
The rear mount of the gas tank. This is welded on both sides of the tank. I will make a other bolt for this place, the devil is in the details.